Soda-lime-silica glass composition with heat resistant properties

摘要

Glass composition consists of in wt.%: 45-68 SiO2; 0-20 Al2O3; 0-20 ZrO2; 0-10 B2O3; 2-12 Na2O; 3.5-9 K2O; 1-13 CaO; 0-8 MgO. The sum of SiO2, Al2O3 and ZrO2 is max. 70% and the sum of Al2O3 and ZrO2 is at least 8%. The glass may also contain BaO and/or SrO such that MgO+CaO+BaO+SrO is 11-30%. The glass has a strain point of at least 530 deg C and an expansion coefficient of 80-90 x 10<-7>/ deg C.